Turbine engine and containment assembly for use in a turbine engine

ABSTRACT

A turbine engine that includes an engine casing including a shell and an angel wing member. The angel wing member includes a base defined at the shell, a tip positioned distal from the base, and a first side and a second side that define a thickness of the angel wing member. The thickness of the angel wing member is non-uniform between the base and the tip.

BACKGROUND

The present disclosure relates generally to turbine engines and, morespecifically, to a rotor section containment assembly having an improvedload path transition between components of the assembly.

At least some known gas turbine engines, such as aircraft engines,include a stator assembly that extends circumferentially about a rotorassembly of the turbine engine. Known rotor assemblies include at leastone row of rotor blades that extend radially outward from a blade root,for example, such that the rotor blades rotate proximate the statorassembly of the turbine engine. At least some known stator assembliesinclude a soft wall containment assembly that facilitates providingrotor containment during unlikely events, such as an unexpectedblade-out condition. The soft wall containment assembly generallyincludes an engine casing, a honeycomb structure coupled to the enginecasing, and a carbon fiber backsheet that extends across the honeycombstructure and a portion of the engine casing. More specifically, atleast some known engine casings include an annular angel wing structurecoupled to the backsheet. Annular angel wing structures are typically aconstant thickness, and provide a potential concentrated load path tothe backsheet in the event the engine casing is damaged, such as duringan unexpected blade-out condition.

BRIEF DESCRIPTION

In one aspect, a turbine engine is provided. The turbine engine includesan engine casing including a shell and an angel wing member. The angelwing member includes a base defined at the shell, a tip positioneddistal from the base, and a first side and a second side that define athickness of the angel wing member. The thickness of the angel wingmember is non-uniform between the base and the tip.

In one embodiment, the angel wing member is tapered such that thethickness of the angel wing member is progressively reduced from thebase to the tip.

In one embodiment, a notch is formed in the angel wing member to reducethe thickness of the angel wing member.

In one embodiment, a backsheet extends over the first side of the angelwing member, wherein the notch is formed on the second side of the angelwing member.

In one embodiment, the angel wing member is oriented obliquely relativeto the shell such that a cavity is at least partially defined betweenthe shell and the angel wing member.

In one embodiment, a honeycomb structure is positioned within thecavity, wherein the backsheet further extends over the honeycombstructure and across the angel wing member, and a layer of containmentmaterial extending over the backsheet.

In one embodiment, an array of rotor blades is positioned radiallyinward from the engine casing, wherein the array of rotor blades and thelayer of containment material are axially aligned relative to acenterline of the turbine engine.

In one embodiment, the engine casing includes a fan case.

In another aspect, a containment assembly for use in a turbine engine isprovided. The containment assembly includes an engine casing including ashell and an angel wing member. The angel wing member includes a basedefined at the shell, a tip positioned distal from the base, and a firstside and a second side that define a thickness of the angel wing member.The assembly further includes a honeycomb structure coupled to theshell, and a backsheet including a first portion extending across theangel wing member and a second portion extending across the honeycombstructure. The thickness of the angel wing member is non-uniform betweenthe base and the tip.

In one embodiment, a layer of containment material extends over thebacksheet.

In one embodiment, the containment material includes an aramid material.

In one embodiment, the angel wing member is tapered such that thethickness of the angel wing member is progressively reduced from thebase to the tip.

In one embodiment, a notch is formed in the angel wing member to reducethe thickness of the angel wing member.

In one embodiment, the backsheet extends over the first side of theangel wing member, and wherein the notch is formed on the second side ofthe angel wing member.

In yet another aspect, a method of forming a containment assembly foruse in a turbine engine is provided. The method includes coupling ahoneycomb structure to an engine casing, wherein the engine casingincludes a shell and an angel wing member including a base defined atthe shell and a tip positioned distal from the base. The method alsoincludes coupling a backsheet to the angel wing member and the honeycombstructure, wherein the backsheet includes a first portion extendingacross the angel wing member and a second portion extending across thehoneycomb structure. The method further includes forming the angel wingmember with a non-uniform thickness to modify a stiffness of the angelwing member such that stress concentrations formed in the backsheetinduced from the angel wing member are distributed across the firstportion of the backsheet.

In one embodiment, forming the angel wing member includes tapering theangel wing member such that a thickness of the angel wing member isprogressively reduced from the base to the tip.

In one embodiment, forming the angel wing member includes forming anotch in the angel wing member to reduce a thickness of the angel wingmember.

In one embodiment, the angel wing member includes a first side and asecond side, and the method includes extending the backsheet across thefirst side of the angel wing member, and forming the notch on the secondside of the angel wing member.

In one embodiment, the method further includes extending a layer ofcontainment material across the backsheet.

In one embodiment, the method further includes forming the layer ofcontainment material from an aramid material.

DRAWINGS

These and other features, aspects, and advantages of the presentdisclosure will become better understood when the following detaileddescription is read with reference to the accompanying drawings in whichlike characters represent like parts throughout the drawings, wherein:

FIG. 1 is a schematic illustration of an exemplary turbine engine;

FIG. 2 is a cross-sectional illustration of an exemplary containmentassembly that may be used in the turbine engine shown in FIG. 1;

FIG. 3 is a cross-sectional illustration of a portion of the containmentassembly shown in FIG. 2 taken along Area 3, in accordance with a firstembodiment of the disclosure;

FIG. 4 is a cross-sectional illustration of the portion of thecontainment assembly shown in FIG. 3, in accordance with a secondembodiment of the disclosure;

FIG. 5 is a cross-sectional illustration of the portion of thecontainment assembly shown in FIG. 3, in accordance with a thirdembodiment of the disclosure; and

FIG. 6 is a cross-sectional illustration of the portion of thecontainment assembly shown in FIG. 3, in accordance with a fourthembodiment of the disclosure.

Unless otherwise indicated, the drawings provided herein are meant toillustrate features of embodiments of the disclosure. These features arebelieved to be applicable in a wide variety of systems comprising one ormore embodiments of the disclosure. As such, the drawings are not meantto include all conventional features known by those of ordinary skill inthe art to be required for the practice of the embodiments disclosedherein.

DETAILED DESCRIPTION

In the following specification and the claims, reference will be made toa number of terms, which shall be defined to have the followingmeanings.

The singular forms “a”, “an”, and “the” include plural references unlessthe context clearly dictates otherwise.

“Optional” or “optionally” means that the subsequently described eventor circumstance may or may not occur, and that the description includesinstances where the event occurs and instances where it does not.

Approximating language, as used herein throughout the specification andclaims, may be applied to modify any quantitative representation thatcould permissibly vary without resulting in a change in the basicfunction to which it is related. Accordingly, a value modified by a termor terms, such as “about”, “approximately”, and “substantially”, are notto be limited to the precise value specified. In at least someinstances, the approximating language may correspond to the precision ofan instrument for measuring the value. Here and throughout thespecification and claims, range limitations may be combined and/orinterchanged. Such ranges are identified and include all the sub-rangescontained therein unless context or language indicates otherwise.

As used herein, the terms “axial” and “axially” refer to directions andorientations that extend substantially parallel to a centerline of theturbine engine. Moreover, the terms “radial” and “radially” refer todirections and orientations that extend substantially perpendicular tothe centerline of the turbine engine. In addition, as used herein, theterms “circumferential” and “circumferentially” refer to directions andorientations that extend arcuately about the centerline of the turbineengine.

Embodiments of the present disclosure relate to a rotor sectioncontainment assembly that provides an improved load path transitionbetween components of the assembly. More specifically, the containmentassembly described herein includes an engine casing, such as a fan case,including a shell and an angel wing member that extends from the shell.The angel wing member is an annular structure and includes a basedefined at the shell and a tip positioned distal from the base. Thecontainment assembly also includes a backsheet extending over the angelwing member such that an angled region is formed in the backsheet at thetip of the angel wing member. The angel wing member described hereinincludes one or more design features that facilitate limiting damage tothe backsheet induced by the angel wing member in the event the angelwing member is forced radially outward towards the backsheet, such asduring an unexpected blade-out condition. The angel wing design featuresinclude a contoured tip and a non-uniform thickness. As such, stressconcentrations in the backsheet induced from the angel wing member arefacilitated to be mitigated, and a smooth load path transition isprovided between the angel wing member and the backsheet, therebyreducing the likelihood of damage to the backsheet.

While the following embodiments are described in the context of aturbofan engine, it should be understood that the systems and methodsdescribed herein are also applicable to turboprop engines, turboshaftengines, turbojet engines, and ground-based turbine engines, forexample.

FIG. 1 is a schematic diagram of an exemplary turbine engine 10including a fan assembly 12, a low-pressure or booster compressorassembly 14, a high-pressure compressor assembly 16, and a combustorassembly 18. Fan assembly 12, booster compressor assembly 14,high-pressure compressor assembly 16, and combustor assembly 18 arecoupled in flow communication. Turbine engine 10 also includes ahigh-pressure turbine assembly 20 coupled in flow communication withcombustor assembly 18 and a low-pressure turbine assembly 22. Fanassembly 12 includes an array of fan blades 24 extending radiallyoutward from a rotor disk 26. Low-pressure turbine assembly 22 iscoupled to fan assembly 12 and booster compressor assembly 14 through afirst drive shaft 28, and high-pressure turbine assembly 20 is coupledto high-pressure compressor assembly 16 through a second drive shaft 30.Turbine engine 10 has an intake 32 and an exhaust 34. Turbine engine 10further includes a centerline 36 about which fan assembly 12, boostercompressor assembly 14, high-pressure compressor assembly 16, andturbine assemblies 20 and 22 rotate.

During operation, air entering turbine engine 10 through intake 32 ischanneled through fan assembly 12 towards booster compressor assembly14. Compressed air is discharged from booster compressor assembly 14towards high-pressure compressor assembly 16. Highly compressed air ischanneled from high-pressure compressor assembly 16 towards combustorassembly 18, mixed with fuel, and the mixture is combusted withincombustor assembly 18. High temperature combustion gas generated bycombustor assembly 18 is channeled towards turbine assemblies 20 and 22.Combustion gas is subsequently discharged from turbine engine 10 viaexhaust 34.

FIG. 2 is a cross-sectional illustration of an exemplary containmentassembly 100 that may be used in turbine engine 10 (shown in FIG. 1). Inthe exemplary embodiment, containment assembly 100 includes an enginecasing 102 (hereinafter also referred to as a “fan case”) including ashell 104 and an angel wing member 106, and a honeycomb structure 108coupled to shell 104. More specifically, angel wing member 106 isoriented obliquely relative to shell 104 such that a cavity 110 is atleast partially defined between shell 104 and angel wing member 106.Honeycomb structure 108 is positioned within cavity 110 to provide noiseattenuation when turbine engine 10 is in operation.

Containment assembly 100 further includes a backsheet 112 extending overangel wing member 106 and honeycomb structure 108. More specifically,backsheet 112 includes a first portion 114 extending across angel wingmember 106, a second portion 116 extending across honeycomb structure108, and an angled region 118 defined between first portion 114 andsecond portion 116. In addition, backsheet 112 is coupled to angel wingmember 106 with a layer 120 (shown in FIGS. 3-6) of adhesive material.

In the exemplary embodiment, angel wing member 106 and backsheet 112 arefabricated from any material that enables containment assembly 100 tofunction as described herein. For example, angel wing member 106 isfabricated from a metallic material, such as aluminum, and backsheet 112is fabricated from a composite material, such as a carbon fiberreinforced polymer (CFRP) material. As such, and as will be explained inmore detail below, a thickness of angel wing member 106 is tailored tofacilitate reducing a metallic material-to-composite material ratio atan interface defined between angel wing member 106 and backsheet 112 andthus facilitates providing a smooth load path transition therebetween.

Moreover, backsheet 112 provides a surface in which one or moresubsequent layers of material may be positioned circumferentially aboutengine casing 102. For example, containment assembly 100 also includes alayer 122 of containment material extending over backsheet 112. Thecontainment material may be any material that enables containmentassembly 100 to function as described herein. An exemplary containmentmaterial includes, but is not limited to, an aramid material (i.e.,Kevlar®).

In the exemplary embodiment, an array of rotor blades 124, such as fanblades 24 (shown in FIG. 1), is positioned radially inward from enginecasing 102. The array of rotor blades 124 and layer 122 of containmentmaterial are axially aligned relative to centerline 36 (shown in FIG. 1)of turbine engine 10. More specifically, layer 122 of containmentmaterial traverses a leading edge 126 and a trailing edge 127 of rotorblades 124. As such, in the event of an unexpected blade-out condition,layer 122 of containment material is positioned to impede radiallyoutward movement of rotor blades 124.

FIGS. 3-6 are cross-sectional illustrations of a portion of containmentassembly 100 (shown in FIG. 2) taken along Area 3, in accordance withdifferent embodiments of the disclosure. As described above, angel wingmember 106 includes one or more design features that facilitate limitingdamage to backsheet 112 induced by angel wing member 106. In theexemplary embodiment, referring to FIG. 3, angel wing member 106includes a base 126 defined at shell 104 and a tip 128 positioned distalfrom base 126. Moreover, as described above, backsheet 112 extends overangel wing member 106 such that angled region 118 is defined inbacksheet 112 at an interface with tip 128. In some embodiments, tip 128is contoured to mitigate stress concentrations in angled region 118induced from tip 128, such as when angel wing member 106 is forcedradially outward during an unexpected blade-out condition.

In the exemplary embodiment, tip 128 is contoured with any radius sizethat enables containment assembly to function as described herein. Forexample, in one embodiment, tip 128 is contoured with a radius size ofat least about 0.01 inch. Referring again to FIG. 3, tip 128 iscontoured with a full radius defined between a first side 130 and asecond side 132 of angel wing member 106. Referring to FIG. 4, tip 128is contoured with a half radius defined on first side 130 of angel wingmember 106 and oriented towards backsheet 112. Referring to FIG. 5, tip128 is contoured with a chamfer defined on first side 130 of angel wingmember 106 and oriented towards backsheet 112. As such, a bluntinterface is defined between angel wing member 106 and backsheet 112 inthe event angel wing member 106 is deflected radially outward towardsbacksheet 112, thereby reducing stress concentrations in angled region118 when compared to an angel wing member having a sharp-edged tip.

Moreover, in the exemplary embodiment, first side 130 and second side132 of angel wing member 106 define a thickness of angel wing member106. In one embodiment, the thickness of angel wing member 106 isnon-uniform between base 126 and tip 128. Defining the thickness ofangel wing member 106 in a non-uniform manner facilitates tailoring thestiffness of angel wing member 106, and also facilitates reducing themetallic material-to-composite material ratio at the interface definedbetween angel wing member 106 and backsheet 112. As such, a gradual loadtransfer is formed between angel wing member 106 and backsheet 112 inthe event angel wing member 106 is forced radially outward towardsbacksheet 112. For example, reducing the stiffness of angel wing member106 facilitates distributing stress concentrations in backsheet 112induced from angel wing member 106 across first portion 114 of backsheet112, rather than having the stress concentrations primarily located atangled region 118.

In the exemplary embodiment, referring to FIG. 3, angel wing member 106is tapered such that the thickness of angel wing member 106 isprogressively reduced from base 126 to tip 128. Referring to FIG. 6, atleast one notch 134 is formed in angel wing member 106 to reduce thethickness of angel wing member 106. More specifically, backsheet 112extends across first side 130 of angel wing member 106, and notch 134 isformed on second side 132 of angel wing member 106.

An exemplary technical effect of the assembly and methods describedherein includes at least one of: (a) providing containment of a rotorassembly; (b) providing a smooth load path transition between metallicand composite components in a containment assembly; and (c) reducing thelikelihood of damage to a backsheet in the containment assembly in theevent an angel wing member is forced radially outward towards thebacksheet.

Exemplary embodiments of a containment assembly for use with a turbineengine and related components are described above in detail. Theassembly is not limited to the specific embodiments described herein,but rather, components of systems and/or steps of the methods may beutilized independently and separately from other components and/or stepsdescribed herein. For example, the configuration of components describedherein may also be used in combination with other processes, and is notlimited to practice with a fan section of a turbine engine. Rather, theexemplary embodiment can be implemented and utilized in connection withmany applications where providing smooth load transition betweencomponent in an assembly is desired.

Although specific features of various embodiments of the presentdisclosure may be shown in some drawings and not in others, this is forconvenience only. In accordance with the principles of embodiments ofthe present disclosure, any feature of a drawing may be referencedand/or claimed in combination with any feature of any other drawing.

This written description uses examples to disclose the embodiments ofthe present disclosure, including the best mode, and also to enable anyperson skilled in the art to practice embodiments of the presentdisclosure, including making and using any devices or systems andperforming any incorporated methods. The patentable scope of theembodiments described herein is defined by the claims, and may includeother examples that occur to those skilled in the art. Such otherexamples are intended to be within the scope of the claims if they havestructural elements that do not differ from the literal language of theclaims, or if they include equivalent structural elements withinsubstantial differences from the literal languages of the claims.

What is claimed is:
 1. A turbine engine comprising: an engine casingcomprising: a shell; and an angel wing member comprising a base definedat said shell, a tip positioned distal from said base, and a first sideand a second side that define a thickness of said angel wing member,wherein the thickness of said angel wing member is non-uniform betweensaid base and said tip.
 2. The turbine engine in accordance with claim1, wherein said angel wing member is tapered such that the thickness ofsaid angel wing member is progressively reduced from said base to saidtip.
 3. The turbine engine in accordance with claim 1, wherein a notchis formed in said angel wing member to reduce the thickness of saidangel wing member.
 4. The turbine engine in accordance with claim 3further comprising a backsheet extending over said first side of saidangel wing member, wherein said notch is formed on said second side ofsaid angel wing member.
 5. The turbine engine in accordance with claim1, wherein said angel wing member is oriented obliquely relative to saidshell such that a cavity is at least partially defined between saidshell and said angel wing member.
 6. The turbine engine in accordancewith claim 5 further comprising: a honeycomb structure positioned withinsaid cavity, wherein said backsheet further extends over said honeycombstructure and across said angel wing member; and a layer of containmentmaterial extending over said backsheet.
 7. The turbine engine inaccordance with claim 6 further comprising an array of rotor bladespositioned radially inward from said engine casing, wherein said arrayof rotor blades and said layer of containment material are axiallyaligned relative to a centerline of the turbine engine.
 8. The turbineengine in accordance with claim 1, wherein said engine casing comprisesa fan case.
 9. A containment assembly for use in a turbine engine, saidcontainment assembly comprising: an engine casing comprising: a shell;and an angel wing member comprising a base defined at said shell, a tippositioned distal from said base, and a first side and a second sidethat define a thickness of said angel wing member; a honeycomb structurecoupled to said shell; and a backsheet comprising a first portionextending across said angel wing member and a second portion extendingacross said honeycomb structure, wherein the thickness of said angelwing member is non-uniform between said base and said tip.
 10. Thecontainment assembly in accordance with claim 9 further comprising alayer of containment material extending over said backsheet.
 11. Thecontainment assembly in accordance with claim 10, wherein thecontainment material includes an aramid material.
 12. The containmentassembly in accordance with claim 9, wherein said angel wing member istapered such that the thickness of said angel wing member isprogressively reduced from said base to said tip.
 13. The containmentassembly in accordance with claim 9, wherein a notch is formed in saidangel wing member to reduce the thickness of said angel wing member. 14.The containment assembly in accordance with claim 13, wherein saidbacksheet extends over said first side of said angel wing member, andwherein said notch is formed on said second side of said angel wingmember.
 15. A method of forming a containment assembly for use in aturbine engine, said method comprising: coupling a honeycomb structureto an engine casing, wherein the engine casing includes a shell and anangel wing member including a base defined at the shell and a tippositioned distal from the base; coupling a backsheet to the angel wingmember and the honeycomb structure, wherein the backsheet includes afirst portion extending across the angel wing member and a secondportion extending across the honeycomb structure; and forming the angelwing member with a non-uniform thickness to modify a stiffness of theangel wing member such that stress concentrations formed in thebacksheet induced from the angel wing member are distributed across thefirst portion of the backsheet.
 16. The method in accordance with claim15, wherein forming the angel wing member comprises tapering the angelwing member such that a thickness of the angel wing member isprogressively reduced from the base to the tip.
 17. The method inaccordance with claim 15, wherein forming the angel wing membercomprises forming a notch in the angel wing member to reduce a thicknessof the angel wing member.
 18. The method in accordance with claim 17,wherein the angel wing member includes a first side and a second side,said method further comprising: extending the backsheet across the firstside of the angel wing member; and forming the notch on the second sideof the angel wing member.
 19. The method in accordance with claim 15further comprising extending a layer of containment material across thebacksheet.
 20. The method in accordance with claim 19 further comprisingforming the layer of containment material from an aramid material.